Think this is a classic example of needing to know the reasons why things are done a particular way.
If a child is unable to use an Infant Life-jacket an Adult Life-jacket is used instead. But in order for the child to fit properly into and be correctly fitted on certain types of life-jacket they MUST be inflated first, then deflated (partially or fully) before returning to their seat.
We're all very much aware of what happened in Ethiopia.
Having a child in certain types of life jacket with out following the steps could result in the child not being able to breath as it inflates around the child's neck and face. Coming out of the life-jacket or like bubblyguy said if not deflated child floats to the ceiling of the a/c.
Its up to the parents to remember that they will need to manually inflate the life-jacket again.
Manuals might be printed in black and white but life is most certainly in colour
